HOUSTON, April 28 (Reuters) - A unit in Colombia of
Toronto-listed oil company Pacific Rubiales launched a
tender to sell two 1 million barrel cargoes of Castilla heavy
crude for delivery in June at Covenas port, according to a
document seen by Reuters on Monday.

Pacific last month sold five Castilla cargoes, 1 million
barrels each, and a 500,000 barrel Vasconia crude cargo on the
open market, but this month has not offered any Vasconia since
the Cano Limon pipeline was halted a month ago.

The company detailed in the invitation that the first
Castilla cargo will be loaded on June 1-15 and the second one on
June 16-30. Sellers will include any combination of Pacific's
subsidiaries: Meta Petroleum, C&C Energy Barbados, Pacific
Stratus Energy and Petrominerales.

Interested companies should submit bids until April 29 and
they must be indexed to WTI or Brent crudes front month prices.

Pacific Rubiales is the largest private oil producer in
Colombia.
(Reporting by Marianna Parraga; Editing by Terry Wade)